Living in a small apartment complex in the Strand, Cashan was the most respected music critic in London, spending much of his time at concerts, and writing reviews when he got back home. Often these reviews would be scathing and unkind, which his readers enjoyed greatly. In 1868, Cashan attended a concert of the Aldwych Chamber Orchestra, writing a series of particularly negative reviews, in which he personally insulted the First Violin of the orchestra.
Unbeknownst to him, the First Violin of the Aldwych Chamber Orchestra, David Golden, was his downstairs neighbor. When Cashan's reviews led to the disbanding of the Orchestra, Golden fashioned a poisoned candle, cut the gaslines in the apartment building, and handed out the candles to all his neighbors, ensuring that Cashan got the poisoned one.
The following morning, Cashan was found dead in his room, and Golden, as well as all the other inhabitants of the building, was questioned by the Assassins Jacob and Evie Frye. When Golden was eventually confronted with all the evidence pointing towards him, he confessed that he had committed the murder out of revenge for Cashan's scathing reviews, which ruined the careers of many musicians.